According to Myers, he had to enable a Chrome flag — chrome://flags/#instant-tethering — on the Chrome OS Dev channel version 73.0.3669.0. Once activated, Myers was able to add his Note 9 through the ‘Connected devices’ setting on his Chromebook. Finally, Myers had to accept the prompt to turn on Instant Tethering when he disconnected from Wi-Fi.

However, the feature doesn’t appear to work for everyone, even on Dev channel version 73. It’s possible Instant Tethering is rolling out through a server-side update, or there could be another requirement that we don’t yet know about.

Google says on its support page that you need Chrome OS 70 and higher, Android 7.1 and up, and the same Google account on both devices. Further, Google says your mobile data plan must support tethering.

The support page still notes the use of a Pixel phone and at the time of writing doesn’t say you can use other phones.